    /*
     *      * Copyright 2006 Sun Microsystems, Inc.  All Rights Reserved.
     *           *
     *                * Redistribution and use in source and binary forms, with or without
     *                     * modification, are permitted provided that the following conditions
     *                          * are met:
     *                               *
     *                                    *   - Redistributions of source code must retain the above copyright
     *                                         *     notice, this list of conditions and the following disclaimer.
     *                                              *
     *                                                   *   - Redistributions in binary form must reproduce the above copyright
     *                                                        *     notice, this list of conditions and the following disclaimer in the
     *                                                             *     documentation and/or other materials provided with the distribution.
     *                                                                  *
     *                                                                       *   - Neither the name of Sun Microsystems nor the names of its
     *                                                                            *     contributors may be used to endorse or promote products derived
     *                                                                                 *     from this software without specific prior written permission.
     *                                                                                      *
     *                                                                                           * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
     *                                                                                                * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     *                                                                                                     * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     *                                                                                                          * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
     *                                                                                                               * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     *                                                                                                                    * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     *                                                                                                                         * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     *                                                                                                                              * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     *                                                                                                                                   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     *                                                                                                                                        * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     *                                                                                                                                             * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     *                                                                                                                                                  */

    import java.security.KeyStore;
import java.security.MessageDigest;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

    public class InstallCert {

        public static void main(String[] args) throws Exception {
            String host;
            int port;
            char[] passphrase;
            if ((args.length == 1) || (args.length == 2)) {
                String[] c = args[0].split(":");
                host = c[0];
                port = (c.length == 1) ? 443 : Integer.parseInt(c[1]);
                String p = (args.length == 1) ? "changeit" : args[1];
                passphrase = p.toCharArray();
            } else {
                System.out
                        .println("Usage: java InstallCert <host>[:port] [passphrase]");
                return;
            }

            File file = new File("jssecacerts");
            if (file.isFile() == false) {
                char SEP = File.separatorChar;
                File dir = new File(System.getProperty("java.home") + SEP + "lib"
                        + SEP + "security");
                file = new File(dir, "jssecacerts");
                if (file.isFile() == false) {
                    file = new File(dir, "cacerts");
                }
            }
            System.out.println("Loading KeyStore " + file + "...");
            InputStream in = new FileInputStream(file);
            KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
            ks.load(in, passphrase);
            in.close();

            SSLContext context = SSLContext.getInstance("TLS");
            TrustManagerFactory tmf = TrustManagerFactory
                    .getInstance(TrustManagerFactory.getDefaultAlgorithm());
            tmf.init(ks);
            X509TrustManager defaultTrustManager = (X509TrustManager) tmf
                    .getTrustManagers()[0];
            SavingTrustManager tm = new SavingTrustManager(defaultTrustManager);
            context.init(null, new TrustManager[]{tm}, null);
            SSLSocketFactory factory = context.getSocketFactory();

            System.out
                    .println("Opening connection to " + host + ":" + port + "...");
            SSLSocket socket = (SSLSocket) factory.createSocket(host, port);
            socket.setSoTimeout(10000);
            try {
                System.out.println("Starting SSL handshake...");
                socket.startHandshake();
                socket.close();
                System.out.println();
                System.out.println("No errors, certificate is already trusted");
            } catch (SSLException e) {
                System.out.println();
                e.printStackTrace(System.out);
            }

            X509Certificate[] chain = tm.chain;
            if (chain == null) {
                System.out.println("Could not obtain server certificate chain");
                return;
            }

            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    System.in));

            System.out.println();
            System.out.println("Server sent " + chain.length + " certificate(s):");
            System.out.println();
            MessageDigest sha1 = MessageDigest.getInstance("SHA1");
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            for (int i = 0; i < chain.length; i++) {
                X509Certificate cert = chain[i];
                System.out.println(" " + (i + 1) + " Subject "
                        + cert.getSubjectDN());
                System.out.println("   Issuer  " + cert.getIssuerDN());
                sha1.update(cert.getEncoded());
                System.out.println("   sha1    " + toHexString(sha1.digest()));
                md5.update(cert.getEncoded());
                System.out.println("   md5     " + toHexString(md5.digest()));
                System.out.println();
            }

            System.out
                    .println("Enter certificate to add to trusted keystore or 'q' to quit: [1]");
            String line = reader.readLine().trim();
            int k;
            try {
                k = (line.length() == 0) ? 0 : Integer.parseInt(line) - 1;
            } catch (NumberFormatException e) {
                System.out.println("KeyStore not changed");
                return;
            }

            X509Certificate cert = chain[k];
            String alias = host + "-" + (k + 1);
            ks.setCertificateEntry(alias, cert);

            OutputStream out = new FileOutputStream("jssecacerts");
            ks.store(out, passphrase);
            out.close();

            System.out.println();
            System.out.println(cert);
            System.out.println();
            System.out
                    .println("Added certificate to keystore 'jssecacerts' using alias '"
                            + alias + "'");
        }

        private static final char[] HEXDIGITS = "0123456789abcdef".toCharArray();

        private static String toHexString(byte[] bytes) {
            StringBuilder sb = new StringBuilder(bytes.length * 3);
            for (int b : bytes) {
                b &= 0xff;
                sb.append(HEXDIGITS[b >> 4]);
                sb.append(HEXDIGITS[b & 15]);
                sb.append(' ');
            }
            return sb.toString();
        }

        private static class SavingTrustManager implements X509TrustManager {

            private final X509TrustManager tm;
            private X509Certificate[] chain;

            SavingTrustManager(X509TrustManager tm) {
                this.tm = tm;
            }

            public X509Certificate[] getAcceptedIssuers() {
                throw new UnsupportedOperationException();
            }

            public void checkClientTrusted(X509Certificate[] chain, String authType)
                    throws CertificateException {
                throw new UnsupportedOperationException();
            }

            public void checkServerTrusted(X509Certificate[] chain, String authType)
                    throws CertificateException {
                this.chain = chain;
                tm.checkServerTrusted(chain, authType);
            }
        }

    }  
